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arXiv · 2407.11816

Modal Effect Types

Wenhao Tang·Leo White·Stephen Dolan·Daniel Hillerström·Sam Lindley·Anton Lorenzen
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Abstract

Effect handlers are a powerful abstraction for defining, customising, and composing computational effects. Statically ensuring that all effect operations are handled requires some form of effect system, but using a traditional effect system would require adding extensive effect annotations to the millions of lines of existing code in these languages. Recent proposals seek to address this problem by removing the need for explicit effect polymorphism. However, they typically rely on fragile syntactic mechanisms or on introducing a separate notion of second-class function. We introduce a novel approach based on modal effect types.

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Wenhao Tang, Leo White, Stephen Dolan, Daniel Hillerström, Sam Lindley, Anton Lorenzen. 2024-07-16. Modal Effect Types. https://arxiv.org/abs/2407.11816

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